The present disclosure relates generally to a connector for a foil-shielded twisted pair (FTP) cable, and more particularly to an improved connector including a jack and insulation displacement contact (IDC) assembly with a pair of pushing wings and a lacing cap and twist nut assembly that securely locks the connector and grounds the cable at the same time.
Twisted pair cabling is a form of wiring in which two conductors (wires/cables) are wound together for the purposes of canceling out electromagnetic interference (EMI), electromagnetic radiation from unshielded twisted pair (UTP) wires/cables, crosstalk between neighboring pairs of cable/wire, or radiofrequency interference (RFI). Twisting wires/cables decreases interference because the loop area between the wires is reduced. In balanced pair operation, two wires/cables typically carry equal and opposite signals which are combined by addition at the destination. The common-mode noise from the two wires/cables helps to cancel each other because the two wires have similar amounts of EMI that are 180 degrees out of phase.
In order to reduce interference further and other sources of signal deterioration, electrical wires/cables often further include an insulating jacket surrounding each individual wire, a metal foil or braided sheath surrounding twisted wire/cable pairs and a drain wire. Twisted pair wires/cables are often shielded in attempt to prevent electromagnetic interference, but, because the shielding is made of metal, shielding may also serve as a ground. However, a shielded or screened twisted pair wire/cable usually has a special grounding wire added called a drain wire. A drain wire directs extraneous signals to the ground. Shielding can be applied to individual wire/cable pairs, or to a collection of pairs. When shielding is applied to the collection of all pairs of wires/cables present, the shielding is referred to as screening. Shielding must usually be grounded for the shielding to function properly. Cables which include at least one twisted wire/cable pair (in which the wires/cables may be individually insulated), a drain wire, a metal foil or sheath surrounding the twisted pair(s) and drain wire, and an insulating jacket surrounding the wires/cables and the metal foil or sheath are commonly referred to as foil-shielded twisted pair (FTP) cables.
An FTP cable may be terminated by a connector assembly, such as a jack, that is adapted to operatively engage a mating connector, such as a plug. A jack typically includes a housing, sometimes made from several individual parts, that is manufactured from non-conductive material(s). A jack assembly may include a metal wrap to provide similar interference prevention as the metal foil or sheath in an FTP cable. Stated differently, a metal wrap in a jack housing, or other similarly functioning mechanism, may serve as a continuation of the foil wrap or shielding of an FTP cable so that continuity of shielding is provided to and through the connection into the jack housing. In such shielded jacks, the drain wire of an FTP cable may be secured to the metal wrap. A mating shield plug may be engaged within a shielded jack, and the metal shield of the jack may contact the metal wrap of the jack, thereby providing electrical continuity.
An end user of a connector assembly (also known as a jack) is the installer. An end user typically connects an FTP cable to a corresponding jack manually—i.e., by physically exposing the wire/cable of the twisted pair(s), exposing the terminals located inside the jack housing if they are not already exposed, connecting the wires/cables to the terminals, and, finally, assembling the jack into its final form. The final form of a connector assembly commonly includes a covering or other protecting mechanism over the wire-terminal connections.
PCT Publication WO 2008/081087 discloses a socket to be mounted on a multi-conductor cable and includes a removable comb defining a central channel, a connection terminal block, and a locking screw and nut assembly. Here, the screw is fixedly mounted on the removable comb for axial translation and rotation relative to the axis (X) of the socket. The terminal block includes two columns of posts that prevent the rotation of the comb. The screw has two helical slopes capable of engaging corresponding helical notches in the columns. As the screw is rotated, the helical slopes and helical notches interact and a torque is created. This torque causes translation between the screw and the terminal block, ultimately resulting in a secure connection between the screw, comb and terminal block. The contents of the PCT application WO 2008/081087 is hereby incorporated herein in its entirety.
U.S. Pat. No. 7,758,383 recently issued to the inventors herein discloses FTP connector assemblies including a deflectable contact and a cam nut. The cam nut engages a cam member that passes through and couples the various housing elements together and compresses the deflectable contact to engage with a drain wire and/or shielding of an FTP cable. The contents of our earlier patent is incorporated herein in its entirety.
U.S. Pat. No. 7,413,464 to Chen discloses a locking socket with two pivotable pressing elements to push a terminal pusher to engage each wire in the cable into a corresponding IDC. A cable tie or similar tying element is then tied around the closed pressing elements and the cable to prevent opening of the pressing elements and maintain the engagement of the terminal pusher in place. The contents of Chen U.S. Pat. No. 7,413,464 is hereby incorporated herein in its entirety.
Another U.S. patent disclosing a terminal connector with pivoting wings is U.S. Pat. No. 5,957,720 to Boudin, the contents of which are incorporated herein by reference in its entirety. The Boudin patent discloses a connector with two jaws to press the wires into the IDC terminals, so as to accomplish the electrical connection. The jaws are not locked as in the Chen Patent and the stranded wires may stripped off from the IDC terminals once the stranded wires are dragged. If the cable with stranded wires is vertical to the socket base, this increases the space needed for the socket base, making this configuration not suitable for use in a server host that occupies a small space.
It is important for an end user to securely connect the FTP wire/cable to the jack housing because a secure connection can prevent the FTP cable from pulling away from the housing and therefore cause the twisted pair wires from disconnecting or disengaging from the terminals located inside the jack housing. As discussed above, to ensure proper functionality it is important that an end user securely engages the subcomponents of a jack to one another, provides continuity of shielding to and through the connection into the jack housing, and provides a secure connection between the terminals of the jack and the individual FTP wires.
Notwithstanding these improvements in a variety of FTP connectors, there remains a need to provide a secure way to provide a connector that is easy to assemble and securely locks the components and grounds the cable in one easy and secure movement.